//把字符串中的小写字母改成大写字母
#include<stdio.h>
#include<ctype.h>
int main()
{
    int i = 0;
    char str[] = "Hello Laura!\n";
    char ch;
    while(str[i])
    {
        ch = str[i];
        if(islower(ch))//判断是否为小写字母
            ch -= 32;
        putchar(ch);
        i ++;
    }
    return 0;
}